Topic: From Sh*tty to Shiny: Sbeckman7's CB350F Cafe Resto

[grcamna2]

I recommend carefully covering over the openings in your crankcases and just propping the engine forward to where the cylinder studs are horizontal and meticulously cleaning each one of those cylinder mounting studs,otherwise that stuff will get into your crankshaft & rod bearings plus inside the cases.

[sbeckman7]

I recommend carefully covering over the openings in your crankcases and just propping the engine forward to where the cylinder studs are horizontal and meticulously cleaning each one of those cylinder mounting studs,otherwise that stuff will get into your crankshaft & rod bearings plus inside the cases.

That's good advice.  There was even more when I first removed the cylinders, and while I did my blow to get all of it away from the crankcase a little bit did go inside    Hoping it will flush out with gratuitous amounts of oil...

[sbeckman7]

Don't use oil to flush your motor, use a fluid like Diesel or Kerosene. It's cheaper and more productive at rinsing away particles.

You need to replace many of those studs. Use a "stud puller" and lots of heat (like cherry red hot) pointed directly at the case where the stud meets it. Use a hammer and give each stud a whack then use the puller to twist out the stud. This will he loosen any stuck studs, and prevent them from snapping off.

When they're corroded like that, they're apt to shear when you re-torque the head nuts to them and better to replace them now then after you've assembled the top end. 

I figured replacement was basically a given haha.  Thanks for those tips for the diesel and stud puller   I might try the 2-nut method first in case I get lucky. 

This little engine sure is turning into a $$$ sucker!!

[sbeckman7]

Good news from the local motorcycle shop!  They took a quick look at the head and said it looks great, advised to simply hone and reinstall.  So I'll be doing that   It will get a bath today followed by some paint prep while I wait for the flex hone to arrive.  I decided to go that route in the interest of saving time/money.  In the end it comes down to me not being worried about the quality gap between that and a rigid stone hone.  I have ordered the flex-hone as well.

[sbeckman7]

I hope you meant they said the bores looked great, not the head  Or did they also inspect the head and valves and gave it a passing grade too?

Oops    I definitely meant to type "bores" instead.  The newly rebuilt head, however, is on its way to me!

[sbeckman7]

Man, for a newbie, you're making really great progress on getting this thing together. Take great care with the rings on the pistons when reinstalling them into the bores. Watch ample YouTube videos on honing, and use lots of cutting fluid (motor oil or better). Some use WD, but I encourage you to use something of a true lubricant or cutting fluid. Produces a better, more even cut.

I will definitely be using cutting oil, in fact I think I already have some   I am assuming I need new piston rings, correct?  Or should the originals stay on as they are already matched with the bores?

[grcamna2]

Go with new oem Honda rings,imo

[sbeckman7]

I assume you are talking about the gap where the rings are open?  I'll look in to that.

I made a mess today but at least I got it on video!  Hopefully this can serve as a reference (yet another one) to anyone curious about walnut-shell blasting and it's effectiveness.  I would summarize that it's great for removing caked on dirt and grime but not effective for oxidation or rust.

Argh is it really impossible to embed youtube videos or am I just doing it wrong?
www.youtube.com/watch?v=nIqUXvgRvwA

With the first one cleaned, I'm thinking about running over to Harbor Freight tonight to try out an ultrasonic cleaner for the other 3 carbs.  I could then compare the results (and return the cleaner if necessary!)


It's hard to see in this picture how effective/ineffective the walnut blaster really is.  It removed all of the dirt, so the parts are "clean," but some surfaces (mainly the bottom carb cap and bracket) are still pretty oxidized so they don't look new.

[grcamna2]

When you're ready to assemble the carbs. after complete cleaning,etc. be sure to put a thread lock agent like red Loctite on the threads of each carb. choke butterfly 'plate',if one of those 2) little screws that hold them on were to get sucked into the engine  it could be catastrophic.

[sbeckman7]

When you're ready to assemble the carbs. after complete cleaning,etc. be sure to put a thread lock agent like red Loctite on the threads of each carb. choke butterfly 'plate',if one of those 2) little screws that hold them on were to get sucked into the engine  it could be catastrophic.

So true!! Good idea.  I won't be removing the other choke butterflies as I was told I "got lucky" getting this one out without stripping anything 

Happy to report I just added the All Balls Racing stem bearing kit (22-1011) to my completed orders list.  $30 on amazon 

[MoMo]

Man, for a newbie, you're making really great progress on getting this thing together. Take great care with the rings on the pistons when reinstalling them into the bores. Watch ample YouTube videos on honing, and use lots of cutting fluid (motor oil or better). Some use WD, but I encourage you to use something of a true lubricant or cutting fluid. Produces a better, more even cut.

There is such a thing as honing oil if you want to go that route.  You only need a minuscule amount per cylinder though

[sbeckman7]

Maybe I'll spring for that then, found a ½ pint on amazon for $11.  Finished prepping the frame for blasting/powder coating this evening by removing the last of the hardware (except for the bottom stem race!) and wire-wheeling off excess rust and dirt.  I think I'm gonna wire wheel the carb caps too   I also plan on grabbing the harbor freight ultrasonic cleaner tonight to try cleaning the other 3 and comparing.

I tried the wire wheel on my rims as well, and the rear has significant corrosion from rust :/  It's built up (not eaten away at the wheel) but I really don't know how to remove it at this point.  It's dark and shiny sitting on top of the chrome.

[sbeckman7]

Don't wire wheel the carb caps or bowls, it's much too abrasive. Use a Green ScotchBrite pad, then follow up with Red and Grey.

Alright, scotchbrite it is then! If I'm lucky I can finish up all the carbs tomorrow   I got the ultrasonic cleaner tonight from Harbor Freight (along with a Pittsburgh torque wrench).  I have to say I'm impressed   I first tried it out with a ring I wear, and within seconds of turning the machine on I could see a small dirt cloud lifted off of the silver.  The engraved inner band - normally blackened from being worn - was completely bright again.  I had to try out some carb pieces next, so I began with the black retaining clip.  It was pretty rusty on one end, so I was curious to see how the cleaner would handle it.  This was the result:

It removed a ton of particles which I then rinsed out of the machine.  Next up was the carb body (the one that I had previously blasted).  Sure enough, clouds instantly exited every port on the carb as the ultrasonic machine did its work:





Video of the action: https://www.youtube.com/watch?v=sUSSfUPDhZs&feature=youtu.be


That's where I stopped for tonight   More to come tomorrow.  I'm thinking I'll hold off reassembling the carbs onto the place because I would like to clean the bracket itself up a bit more.  Maybe I can sand blast it.

[sbeckman7]

You can glass bead blast that holder, but honestly, some rust treatment and ScotchBrites will work well too. If you do blast it, use low pressure, fine media, then immerse in the U/S cleaner to purge any media. The spring mechanism needs to free and clear of grit.

I'm home with no plans tonight, so I may just grab some rust treatment and scotchbrite pads   My feet are pretty tired from standing all day.  Standing in front of the sand blaster!  I was able to do my exhaust clamps, top breather cover, swingarm, kickstand, chain guard, "dash," front engine mount, engine side cover, and most of my frame   Very pleased with the results!! Rust and faded paint just wasn't this bike's look.





An additional update: Carb #1 is almost back together although I am waiting to polish up the top and lower covers.  Some new hardware would be nice too...  My eBay speedo also came in the mail today.  I plan on repainting the outer covers of them but leaving the faded dials for a little character contrast

All my sand blasting was done at the College of Marin, and after some thought I will try to do all my paint/pc work there.  Saves some money and I get to learn a new skill   The only downside is that the open shop is every other week.  For this reason I am still considering having my frame powder coated by someone else for ~150.  It would also ensure that the most visual part of the bike looks professional.  We'll see 

[MoMo]

Looks nice and clean, keep up the good work

[sbeckman7]

Looks nice and clean, keep up the good work

Thank you MoMo!  Tonight I got inspired by iiAtlas's carb brackets and had a go at cleaning mine up (as well as the carb caps).  What started out as a painstaking process involving green scotchbrite and a metal brush turned much better once I decided to give the table-mounted wire wheel a try.  I focused heavily on the areas of the carb bracket that would be seen most (the sides) and didn't bother with the pockets of the casting.  I think once it's installed it'll look far better than how they looked just a few hours ago!  i also took the bold move of carefully and gently wire wheeling the float bowl and top cap of carb #1 and it turned out great.  The green scotchbrite wasn't taking the yellow film off and the wire wheel gave both pieces a nice finish, which I then went over with the scotchbrite.  They now have the bright, brushed satin finish I was hoping for




And my speedo Mileage is almost exactly half of my original speedometer's reading.  I will record both and change it when I open it up, whenever that may be.

[MoMo]

For your exhaust clamps, now that they've been blasted, they need to be re-coated with something else they will rust badly. You can use ceramic-based spray paint, ceramic coating thru a powder coater, or just use Grill Paint (like you can find at the home center to touch up your BBQ) which only seem to come in gloss Black.

If you are having your frame powder coated, you can (but document with pictures) remove the vin tag carefully (drill out the rivets and get new ones) and the powder coat, then replace the original vin tag in its original location. Else, the powder coater may spray over it  There's even an online service where you can have a reproduction tag made that is extremely close to the original, and it comes with new rivets. Use a heat gun and some dental floss to slip behind the stock tag to help release the glue so you don't bend it up removing it.

Cal,  Depot has high temp silver, white, and flat black.     Spence,  little rivets are available on eBay, I may even have a couple laying around that i'd send out to you if I could find them

[grcamna2]

I had my exhaust headpipe to engine clamps powdercoated and after a yr. now it hasn't dulled the gloss at all 

[sbeckman7]

Thanks for the feedback guys. I'll shoot the exhaust clamps with some black high temp paint (the engine will be black as well) to prevent that from happening. My goal is to powder coat pretty much everything that bolts to the frame black, and remember the frame will be getting a clear powder coat so I suppose I could spray over the vin tag as well (but maybe that's not recommended?) I suppose I could powder coat the exhaust clamps black too if I wanted but they may not even get to go on the bike depending on when Chris completed my MotoGP Werks exhaust.

[sbeckman7]

 

One for each of the remaining three carbs I opened today.  They range from bad to completely ruined. 

Here is the first one I opened today:  I decided to blast/clean it anyways, but a major area of concern here is the corroded metal around the brass fitting.  I have no idea if it still seals given that the o-ring is somewhere in that corrosion very close to the top.  For this reason I have not attempted to remove the brass.



The next two both have completely stuck slides (wouldn't budge after I pulled HARD on the throttle lever and tapped it with a small hammer after a 10-min WD40 soak) and the float bowls were filled with horrible rust deposits, looking almost as bad as my speedometer.  Black retainers were rusted to pieces and sitting in the bottom of the float bowls.  I honestly don't think these are usable but I would love to be proven wrong.  They both looked more or less the same so here is a picture of the #2 carb:


I would love some advice here.. not sure what to do.  I can either spend more money and time on these (minimum $100 needed for complete rebuild kit) or for somewhere closer to 300 I can get a newly rebuilt set.  Budget is always on my mind but given how I was able to do the sand blasting myself I have some extra to spend where it's needed.  Thanks for any ideas in advance.

[grcamna2]

I think those carbs. are just good for parts in their cond.  You might try to see if member here 'harisuluv' would have a set of CB350/400F carbs. you could get,or possibly another member.. I would sell a good set to you right away if I had them. 

[MoMo]

GRUESOME!   The one body you cleaned could probably be micro-welded.  Forum member Jim French does that. I just sold 3 carb bodies and miscellaneous 400f parts to forum member cougar

[sbeckman7]

I think I will try to source a new set rather than spend the time and money trying to bring these ones back.. :/  Who's selling?!

[harisuluv]

Hmm... In the future, I would recommend that you never again sand blast carbs. Never.

That area where you have missing metal could have been due to corrosion but if you are removing the gunk with sand, sand removes metal too.

I use soda which won't touch plating, rubber, will not etch the metal at all. And even with that, I have to be careful in that area on the baby fours. There simply isn't that much metal there compared to the bigger bikes and it can be very fragile. I also suspect the metallurgy is a bit different.

Its quite likely most of that metal is gone due to sandblasting. Don't do that.

[sbeckman7]

Hmm... In the future, I would recommend that you never again sand blast carbs. Never.

That area where you have missing metal could have been due to corrosion but if you are removing the gunk with sand, sand removes metal too.

I use soda which won't touch plating, rubber, will not etch the metal at all. And even with that, I have to be careful in that area on the baby fours. There simply isn't that much metal there compared to the bigger bikes and it can be very fragile. I also suspect the metallurgy is a bit different.

Its quite likely most of that metal is gone due to sandblasting. Don't do that.

To clarify, I was blasting with ground walnut shells.  I would never sand blast carbs!  The walnut shells can hardly remove dirt - let alone metal The metal that did erode did so when I tried to (gently) scrape some surface oxidation off.  I found a set on eBay it looks like.. there goes another couple bills